SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30f085e7c394d44024ad25532098541032b1868477b1ca4311c8cd96bfda6c5f' 
  AND token = 'nLDxxuqhR+2Hjm1rq0wIH7OtM9vaml276PX2rMR2Qd8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}